This invention relates to single phase and three phase AC to DC power converters using active control of the input current waveform to draw high quality sinusoidal line currents in phase with the applied line voltages.
Conventional power converters (phase-controlled rectifiers) accepting AC line input voltage and providing a DC output voltage introduce harmonic and reactive currents into the power generation and delivery system. Harmonic and reactive currents do not contribute power to the load, and therefore serve only to cause interference in power and communication systems and generally increase the ratings of the power generation and delivery equipment required for a given amount of power. As the use of electric vehicle battery chargers, adjustable speed AC heat pump drives and adjustable speed appliance drives increases, minimization of harmonics and reactive current becomes particularly important. In mobile power systems such as airborne or space craft power supplies, it is also important to reduce harmonics and reactive currents to minimize the required kVA ratings and therefore the weight of generators.
It is an object of the present invention to provide a single phase and a three phase AC to DC power converter which draw high quality sinusoidal line currents which are in phase with the applied line voltages.